Locking buckle



FIG. 1 is a top perspective view of a locking buckle according to the invention.

FIG. 2 is a top plan view thereof.

FIG. 3 is a side view thereof, the opposing side view being identical.

FIG. 4 is a bottom plan view thereof.

FIG. 5 is a front end view thereof; and,

FIG. 6 is a rear end view thereof.

The broken line portions of the Figures are for illustrative purposes only and form no part of the claimed design. 

The ornamental design for a locking buckle, substantially as shown and described. 